Mounting terminal with fixed and moving rigid jaw members



March 26 l968 I R. E. sTURDlvAN 3,375,409

MOUNTING TERMINAL WITH FIXED AND MOVING RIGID JAW MEMBERS Filed Aug. 9,196.5 2 Sheets-#Sheet l f4 .1255( gramo/YAM,

5gg X//s ,4free/55,151

March 26, 1968 R. E. sTURDnvAN 3,375,409

MOUNTING TERMINAL WITH FIXED AND MOVING RIGID JAW MEMBERS Filed Aug. 9,1965 2 Sheets-Sheet United States Patent Ofice 3,375,409 Patented Mar.26, 1968 3,375,409 t l MOUNTING TERMINAL WITH FIXED AND MOVING RIGID JAWMEMBERS Rex E. Sturdivan, Whittier, Calif., assignor to ZinscoElectrical Products, Los Angeles, Calif., a corporation of CaliforniaFiled Aug. 9, 1965, Ser. No. 478,300 3 Claims. (Cl. 317-104) ABSTRACT FTHE DISCLOSURE A meter mounting terminal with extruded fixed andmovingrigid jaw members and a spring for applying clamping pressure. Anopen top lug design permitting laying in of cable. A unitaryconstruction omitting con tact surfaces except at the meter stab and thecable.

This invention relates to a new and improved meter mount for anelectrical watt-hour meter or the like and, in particular, to a mountingterminal adapted for use in conjunction with similar mounting terminalsfor receiving the stab terminals of a plug-in meter or the like.

It is an object of the invention to provide a mounting terminal for ameter stab or the like having improved performance and reliability andat the same time having reduced cost of manufacture. A further object isto provide a mounting terminal with a unitary structure eleminatingcontact surfaces except of course at the meter ter` minal and at theconductor clamping section. A particular object is to provide a meterterminal having a uniform cross section permitting manufacture byextrusion in a lon-g bar with individual terminals being produced byslicing the extruded bar.

It is an object of the invention to provide a mounting terminal havingtwo rigid jaw members defining a terminal receiving space therebetween,with one of the jaw members movable relative to the other andincorporating a spring means for urging the members together to clampthe meter terminal therebetween. A particular object is to provide sucha structure in which the movable jaw member is pivotally mounted in axed jaw member. An additional object is to provide such a structure, inwhich both jaw members have a uniform cross section permittingmanufacture by extrusion and one in which the pivoting member has asubstantially cylindrical edge for sliding engagement in a mating grooveof the fixed jaw member.

It is an object of the invention to provide a mounting terminalincorporating an open top lug construction for receiving conductorspermitting a conductor to be laid into the conductor groove with alateral movement. A further object is to provide such a constructionwhich may be used with one conductor or with a plurality of conductors.An additional object is to provide such a structure in which thecomponents have longitudinal sliding interengaging members and one inwhich the components can be manufactured by extrusion.

The invention also comprises novel details of construe tion and novelcombinations and arrangements of parts, which will more fully appear inthe course of the following description. The drawings merely show andthe description merely describes preferred embodiments of the presentinvention which are given by way of illustration or example.

In the drawings:

FIG. 1 is a side view of a watt-hour meter mounting structure with themeter shown in phantom lines;

FIG. 2 is a sectional view taken along the line 2--2 of FIG. l;

FIG. 3 is an exploded View of a terminal of FIG. 1; and

FIG. 4 is a bottom view of an alternative form of terminal. y

In the structure of FIG. 1, an insulator block 10 is carried on asupport strip 11 which may be a bracket or may vbe the neutral bus. Theblock 10 is fixed to the support 11 by a 'bolt 13 and a nut 14. Amounting terminal 16 is carried at one end of the block 10 by a bolt 17and nut 18, with the head of the bolt 17 engaging a T-shaped groove inthe terminal 16 and with the terminal resting in a cup-shaped section 20of the block. The block 10 typically may be a plastic molding. Anotherterminal 21 is mounted on the other end of the block 10 and a meter pad22 is formed intermediate the terminals.

Another block 25 identical to the block 10 is mounted on the support 11in spaced relation with the block 10. Meter terminals 26, 27 are carriedon the block 25, the terminal 26 being identical to the terminals 16 and21 while the terminal 27 incorporates an alternative type of conductorengaging section.

A meter 30 may be positioned on the pads 22, 31 with the meter stabs 32,33, 34, 35 engaging the terminals 21, 16, 26, 27, respectively.

Referring to the terminal 16, the terminal structure preferablyincorporates a fixed jaw member 40 and a moving jaw member 41 with themoving member carried on the fixed member so that the wall section 42 ofthe moving member can be moved toward and away from the wall section 43of the xed member. The moving jaw member preferably is pivotally mountedin the fixed jaw member by sliding engagement of a cylindrical edge 44with a corresponding groove 45 in the fixed member, with the groove 45being more than a semicylinder so that the moving member cannot be movedlaterally out of the groove. In the preferred form illustrated, thegroove 4'5 is about three-quarters of ka cylinder.

A spring may be positioned in opposing grooves 48, 49 of the jaw members40, 41, respectively, for urging the wall sections of the two memberstogether to clamp the stab terminal 33 therebetween. Various forms ofsprings can be utilized suoli as a coil spring or the U- shaped leafspring 50.

Means are provided on the terminal for connecting a cable and in analternative form, a bus bar. The preferred structure utilizes an opentop cable lug permitting the cable to be laid in with a lateral cablemovement. With this type of construction, the requirement for threadingends of cables through openings is eliminated.

Also, this open top lug construction permits the laying of a singlelength of cable into a plurality of lugs. The known advantages of busbar construction for junction boxes can be achieved equally wellutilizing cable and the open top lugs.

A conductor groove 60 is provided in the jaw member 40 with clampreceiving grooves 61, 62 disposed on opposite sides of the conductorgroove 60. A clamp member 63 having edges 64, 65 engageable with thegrooves 61, 62, respectively, is positioned over the conductor groove 60after the cable has been inserted. A screw 66 is positioned in athreaded opening in the clamp member 63 for clamping the cable 67 in thegroove 60.

The engagement of the edges 64, 65 of the clamp member 63 with thegrooves 61, 62 of the fixed jaw member 40 provides guidance for thesliding insertion of the clamp member and also serves to prevent removalof the clamp member except by the sliding operation. It should be notedthat while the complete grooves as shown in the drawings are preferred,any form of interengaging shoulder structures could be utilized and theword 3 groove as used herein is intended to cover construction. v

Referring now to the terminal 27, t-he meter stab engaging portionthereof is identical to that of the terminal 1`6, vincluding the wallsection 43 of the fixed jaw member 70, the moving jaw member 41 and thespring 50. The terminal 27 provides for connection to a bus bar 71rather than to a cable, with the conductor clamping `section 72 beingformed as an L-shaped bracket having an opening for a screw 73 whichengages a threaded opening in the bus bar 71. The bus bar may be clampedagainst the block 25 by a screw 76. Where bus lbars are used in place ofcables for the terminals, the support member 11 may be omitted with theblocks 10 and 25 carried on the line and load 'bus bars.

Another form of open top lug construction providing for connection oftwo cables is shown in FIG. 4. Conductor grooves 80, 81 are disposed inparallel in the fixed jaw member 82. The meter stab portion of theterminal shown at the right of FIG. 4 may be the same as that previouslydescribed. An additional T-shaped groove 83 may be provided at the leftedge `of the fixed member 82 for additional mounting support if desired.Slide grooves `85 and 86 may be provided at the outer edges of theconductor grooves and additional grooves 87, 88 may be provided on aT-shaped rib 89 between the two conductor grooves 80, 81. A clamp member90 having edges engageable with the grooves of the fixed jaw mem-ber isslidably positioned over the conductor'grooves and carries screws 91,92, With this arrangement a single cable can be utilized in eithergroove 80 or 81, or two cables can be utilized, providing for highercurrent capacity and/or for interconnection of cables.

The components of the terminal member including the fixed jaw members40, 70, 82, the moving jaw member 41, and the clamp members 63, 90 areof uniform cross section permitting manufacture by extrusion, preferablywith an electrical grade of aluminum alloy. Manufacture ofthe parts iscompleted by slicing the .extruded bar into units of appropriate width.No other machining is required except drilling and tapping of holes forthe screws where utilized. The fixed jaw members 40, 70, 82 are unitarystructures with no contact surfaces to introduce resistance loads, heatlosses and hot spots. The only contacts are at the wall section 43 wherethe meter stab or other conductor Ais pressed against the wall sectionby the moving member, and at the conductor groove or bus bar bracketwhere the conductor or bus `bar is clamped against the fixed jawmem'ber.

Although exemplary embodiments of ythe invention have been disclosed anddiscussed, it 'will be understood that other applications of theinvention are possible and that the embodiments disclosed may besubjected to the shoulder various changes, modifications andsubstitutions without necessarily departing from the spirit of `theinvention.

I claim as my invention:

1. In a mounting terminal for a meter stab or the like, the combinationof .a fixed rigid jaw member having a first wall section;

- 4 a moving rigid jaw member having a second wall section and mountedin said fixed jaw member for pivoting toward and away from said firstwall secn tion defining a terminal space therebetween;

5 spring means engaging said jaw members urging said second wall sectiontoward said first wall section for clamping a terminal membertherebetween; and

means for connecting an electrical conductor to said fixed jaw member.

1 2. In a mounting terminal for a meter stab or the like, thecombination of a unitary fixed rigid jaw member of uniform cross sectionhaving a first wall section, a conductor clamping section, and a morethan semicylindrical groove;

a moving rigid jaw member having a second wall section and asubstantially cylindrical edge slidably mounted in said groove of saidfixed jaw member for pivoting toward and away from said first wallsection defining a terminal space between said wall sections; and

spring means engaging said jaw members urging said second wall sectiontoward said first wall section for clampinga terminal membertherebetween;

said conductor clamping section including means for engaging means forclamping a conductor thereto.

3. In a mounting terminal for a meter stab or the like, the combinationof 2 a fixed jaw member having a first wall section and a conductorclamping section including a conductor groove and a clamp receivinggroove on each side of and parallel with the conductorv groove;

a moving jaw member having a second wall section y and ycarried on saidfixed jaw member for movement toward and away from said first wallsection defining a terminal space between said wall sections andincluding spring means urging said second wall section toward said firstwall section for clamping a terminal member therebetween;

kclamp member having edges slidably engageable with said clamp receivinggrooves for maintaining said clamp member overlying said conductorgroove;

and

means for lengaging a conductor in said conductor `groove and urgingsaid clamp member away from said clamping section of' said fixed jawmember.

References Cited UNITED STATES PATENTS 6/192-8 -Hanna 200--170 5/1955Johansson 339-272 OTHER REFERENCES 5 Hagen, German Application No.1,088,573, publication September 1960.

ROBERT SCHAEFER, Primaryy Examiner.

i D. SMITH, Assistant Examiner. i

